vanEssen CTD-Diver DI28 Series User manual

CTD-Diver® DI28x Series

©May2022VanEssenInstruments.Allrightsreserved. www.vanessen.com
Contactdetails:
Van Essen Instruments B.V.
Delftechpark 20, 2628 XH Delft
Netherlands
Tel: [phone]
Van Essen Instruments - Canada
219Labrador Drive,Suite201, Waterloo
ON, Canada N2K4M8
Tel:[phone]
Van Essen Instruments - USA
4561 Greer Circle, Suite 100, Tucker
GA, UnitedStates 30083
Tel: [phone] (US West)
Tel:[phone](USEast)
Internet:www.vanessen.com
Support: [e-mail]
Copyright© 2022 by VanEssenInstrumentsB.V. All rights reserved.This document contains
proprietary information whichis protected by copyright.Nopartofthis documentmay be
photocopied, reproduced,ortranslated toanotherlanguage withoutthepriorwritten consentof Van
Essen Instruments B.V.
VanEssenInstruments B.V.makes no warranty of anykind with regard tothis material, including,but
not limited to, its fitness for a particular application. VanEssen Instruments B.V. will not be liable for
errors contained herein orfor incidental or consequential damages in connection with the furnishing,
performance, or use ofthis material. In no eventshall Van Essen Instruments B.V. be liable forany
claimfordirect, incidental,or consequentialdamagesarising out of,or inconnectionwith,thesale,
manufacture, delivery, or use of anyproduct. Van Essen Instruments and the Van Essen Instruments
logo, Diver and CTD-Diver are trademarks or registeredtrademarks ofVanEssenInstrumentsB.V.
Vitonisa registered trademark of DuPontDow Elastomers.
Thepresence of the WasteElectrical andElectronicEquipment(WEEE) marking on theproduct
indicatesthat the deviceisnotto be disposed via the municipalwaste collectionsystem of any
member state ofthe European Union. Forproducts under the requirement of WEEE directive
(2012/19/EU), please contact your distributor or local Van EssenInstruments B.V. office for theproper
decontamination informationandtake backprogram, which will facilitatethe proper collection,
treatment, recovery, recycling, and safedisposalof the device.

©May2022VanEssenInstruments.Allrightsreserved. www.vanessen.com
CE COMPLIANCE STATEMENT (EUROPE)
We hereby declare thatthedevice(s) describedbelow arein conformity with thedirectives listed.In
theeventofunauthorizedmodification of anydevices listedbelow, thisdeclarationbecomes invalid.
Type: Datalogger
ProductModel: CTD-Diver(DI281, DI282,DI283, DI284)
Relevant EC Directives and Harmonized Standards:
1999/5/EC R&TTE Directive for Radio andTelecommunications Terminal Equipment in accordance to
annexIII to which thisdirective conform to thefollowingstandards:
Low Voltage Directive per EN60950-1 (2006)+A11 (2011) forProduct Safety testing
standardfor"InformationTechnology Equipment"
EMC Directive EN 301 489-1 V1.8.1 / EN 301 489-17 V1.3.2 Electromagnetic emissionand
immunityfor"InformationTechnology Equipment"
2014/30/EU Electromagnetic Compatibility directive, as amended by EN61326-1:2013
Theproduct(s) to whichthisdeclaration relatesisinconformity withtheessential protection
requirements of 2014/30/EU Electromagnetic Compatibility directive. The products are inconformity
with thefollowing standards and/orother normative documents:
EMC: Harmonized Standards: EN 61326-1:2013 Lab Equipment, EMC
IEC61000-6-3:2007 Emission standard forresidential, commercialand light-industrial
environments
IEC61000-4-2:2009 Electrostatic dischargeimmunity test
IEC61000-4-3:2006 Radiated, radio-frequency, electromagnetic field immunity test
IEC61000-4-4:2012 Electrical fast transient/burst immunity test
IEC61000-4-5:2006 Surge immunity test
IEC61000-4-6: 2014 Immunity to conducted disturbances, induced byradio-frequency fields
IEC61000-4-11:2004 Voltage dips, short interruptions and voltage variations immunity tests
I hereby declarethat the equipment namedabove has been designedto comply withthe relevant
sections oftheabove referenced specifications. Theitems comply withall applicable Essential
Requirements of the Directives.

©May2022VanEssenInstruments.Allrightsreserved. www.vanessen.com
Contents
1Introduction.........................................................................................................................................1
Aboutthis Manual ......................................................................................................................1
OperatingPrinciple....................................................................................................................1
MeasuringWater Level...............................................................................................................2
Measuring Temperature.............................................................................................................4
MeasuringConductivity .............................................................................................................4
CTD-Diver Model.........................................................................................................................6
Factory Calibration Procedure...................................................................................................6
2TechnicalSpecification .......................................................................................................................7
General .......................................................................................................................................7
Environmental............................................................................................................................8
Transportation ...........................................................................................................................8
Temperature...............................................................................................................................8
Pressure......................................................................................................................................9
Conductivity.............................................................................................................................10
SampleIntervaland Methods..................................................................................................10
3CTD-DiverInstallationandMaintenance..........................................................................................13
Introduction .............................................................................................................................13
Configuring and Readingthe CTD-Diver..................................................................................13
Installation ina MonitoringWell..............................................................................................16
Installation in Surface Water....................................................................................................16
Use of CTD-Divers at Varying Elevation...................................................................................17
UseinSeawater........................................................................................................................17
Biofouling.................................................................................................................................17
CTD-Diver Maintenance ...........................................................................................................17
User Conductivity Calibration..................................................................................................17
4AppendixI Use of CTD-Divers at VaryingElevations......................................................................20
5AppendixII CTD-Diver CommunicationProtocol...........................................................................21
Introduction .............................................................................................................................21
SerialPort Settings...................................................................................................................21
FrameFormat...........................................................................................................................21
List of Commands ....................................................................................................................22
6AppendixIII CTD-Diver Accessories................................................................................................27
Diver-Office software ...............................................................................................................27
USBReadingUnit.....................................................................................................................27
Stainless Steel Cable................................................................................................................27
Cable Clip..................................................................................................................................28
DiverCopper Shield..................................................................................................................28
Smart InterfaceCable ..............................................................................................................28
Communication Cable .............................................................................................................29
Diver-Mate ................................................................................................................................29
Diver-Link .................................................................................................................................30

©May 2022VanEssenInstruments.Allrightsreserved. www.vanessen.com
1
1Introduction
The CTD-Diver® isa compact, groundwatermonitoring instrument for continuously measuring level,
temperature and electrical conductivity in groundwater, surface water, and industrial waters.The
data collected canbe used to manage water resources, estimate hydraulic conductivity and other
aquifer conditions. Examples of applications are:
•monitor potable waterrecharge areas for watersupply,
•monitor tailings ponds,dewatering activities and water supply levelsof mines,
•general site investigations for construction, and
•contaminant plume monitoring on spill sites, remediation sites, chemical storage facilities,
landfillsitesandhazardouswaste storagesites.
The CTD-Diver is an easy-to-usedatalogger featuringstate-of-the-art electronics ,a robust high
precision pressure sensor for long term accuracy and a platinum 4-electrode conductivity sensor. The
absolutepressure sensor requires minimalmaintenanceandre-calibration.
The CTD-Diver is a datalogger housed ina cylindrical casing with a suspension eye at the top.The
suspension eye can be unscrewed and is designedtoinstall the CTD-Diver intothemonitoringwell.
Thesuspension eye also protects the opticalconnector. Theelectronics, sensorsandbattery are
installed maintenance-free into thecasing. The CTD-Diver is notdesignedtobe opened.
The name ofthe datalogger, the model number, the measurement range and the serial number are
identified on the sideof the CTD-Diver. This information is etched usinga laser and is consequently
chemically neutral and not erasable.
AboutthisManual
Thismanualcontains information aboutVan Essen Instruments CTD-Diver withpart number DI28x,
seesection 2.5, an instrument designed tomeasure groundwater levels, temperature and electrical
conductivity.
Thischapter containsabriefintroduction tothe CTD- 2
contains thetechnical specifications for the CTD-Diver as wellasguidelines for Divermaintenance.
Chapter3 covers the deployment of Divers. This includes programming the Diver with the Diver-Office
software. Subsequently, installation of Divers inmonitoring wells and in surface water is discussed.
There are threeappendices that describetheuse ofDivers at varyingelevation, theDiver
communication protocol and a list of CTD-Diver accessories.
OperatingPrinciple
The CTD-Diver is a datalogger designed tomeasure water pressure, temperature and conductivity.
Measurements are subsequently stored in the CTD-Diver's internal memory. The CTD-Diver consists of
a pressure sensor designed to measurewater pressure, atemperature sensor, a 4-electrode
conductivity sensor and a battery that powers theelectronics that takes and stores the
measurements. TheCTD-Diver isanautonomous dataloggerthat canbe programmedby theuser. The
CTD-Diver has a completely sealed inert ceramic enclosure. The communication between CTD-Divers
andLaptops/field devicesisbasedonoptical communication.
The CTD-Diver measures the absolute pressure. This means that the pressuresensor not only
measures thewater pressure, but alsothe air pressure pushing onthewater surface. Ifthe air
pressurevaries, the measured water pressurewillthus alsovary, withoutvarying the waterlevel. The

©May 2022VanEssenInstruments.Allrightsreserved. www.vanessen.com
2
air pressure canbe measured by a Baro-Diver and subsequently be usedin theDiver-Office software
to convert the CTD-Diver pressure readings intowater level data.
MeasuringWaterLevel
The CTD-Diver establishes theheight of a watercolumn by measuringthewater pressure usingthe
built-inpressure sensor. As long as theCTD-Diver isnotsubmerged inwateritmeasures atmospheric
pressure: thehigher thewater column thehigher themeasured pressure. The height of thewater
column above theDiver's pressure sensor isdetermined based on themeasured pressure.
Tomeasurethese variationsin atmosphericpressure a Baro-Diverisinstalled for eachsite being
measured. The barometric compensation for these variations in atmospheric pressure can be done
usingtheDiver-Officesoftware, seewww.vanessen.com fora free download.It is also possibletouse
alternativebarometric datasuchas datamadeavailableonline.
The barometrically adjusted water values can be related to a reference point such as the topofthe
monitoring well or Mean Sea Level (MSL) orany other verticalreference datum.
1.3.1 ConvertingDiverDataintoWater Level
This section explains howto calculate the water level in relationto avertical reference datum using
theCTD-Diver and Baro-
The figurebelow represents an example ofa monitoring well inwhich a CTD-Diver has been installed.
In this casewe are therefore interestedin the height ofthe water level(WL) in relationto the vertical
reference datum. If thewater level is situated abovethe reference datum ithas apositive valueanda
negative value ifitis situated below thereference datum.
Thetopofcasing(TOC) is measuredinrelation to the vertical reference datumandis denoted inthe
diagram below asTOC. The CTD-Diver is suspended witha cable with alength CL. If thecable length is
not exactly known, it canbe calculated from a manual measurement as described in section 1.3.2.
TheBaro-Diver measuresthe atmosphericpressure (pbaro) and the CTD-Diver measures the pressure
exerted by thewater column (WC) above the CTD-Diver and theatmospheric pressure (pDiver).

©May 2022VanEssenInstruments.Allrightsreserved. www.vanessen.com
3
The watercolumn (WC) abovethe CTD-Diver can beexpressed as:
   
 (1)
wherepisthepressure incmH2O, g istheaccelerationdue togravity (9.80665 m/s2) and ρisthe
densityofthewater (1,000kg/m3).
Thewaterlevel (WL) in relation to the verticalreference datumcanbe calculatedasfollows:
     (2)
BysubstitutingWC from equation(1)inequation (2) we obtain:
     
 (3)
1.3.2 CalculatingtheCableLengthfromaManualMeasurement
If thecable length is not exactly known,it can bedetermined using a manualmeasurement, see the
figurebelow. The manual measurement(MM)istaken fromthetopofcasing to thewater level. The
value ofthe water levelis positive unless, in exceptional circumstances, the water level issituated
above thetop ofcasing.
Thecablelength can nowbecalculatedas follows:
     (4)
where thewater column (WC)iscalculated based onthe measurements takenbythe CTD-Diver and
theBaro-Diver.
Notes:
•If the pressuremeasured by the CTD-Diver and the Baro-Diver is measured at different points
intime,itisnecessary to interpolate. The Diver-Office software automatically performs this
interpolation.
•It is possibleto enter manual measurements into the Diver-Office software. The software
subsequently automaticallycalculates thecable length.
Example
The top ofcasing is measured to be150cm above the Mean Seal Level(MSL): TOC =150 cm.
The cable length is not exactly known and therefore amanual measurement is taken. It turns
out tobe 120 cm: MM= 120 cm.

©May 2022VanEssenInstruments.Allrightsreserved. www.vanessen.com
4
The CTD-Diver measures a pressure of1,170 cmH2Oand theBaro-Diver measuresa pressure
of1,030cmH2O. Substituting these values into equation (1), results in a watercolumn of 140
cm above the Diver: WC = 140 cm.
Substituting thevalues ofthe manual measurement and thewater columninequation (4)
results in thefollowing cable length: CL =120 +140 = 260cm.
The water level inrelation to MSL can nowbe easily calculated using equation (2):WL = 150
260 +140 =30 cm above MSL.
MeasuringTemperature
AllDivers measure the groundwater temperature. This can,for example, provideinformation about
groundwater flows.
Thetemperature is measured usinga semiconductor sensor. Thissensor notonly measures the
temperature, butalso usesthevalueofthe temperatureat thesametimeto compensate the pressure
sensor andelectronics for theeffects of temperature to ensurethe bestpossible performance.
MeasuringConductivity
Inadditionto water levels andtemperature, theCTD-
conductivity inmilli Siemensper centimeter(mS/cm). A changeinconductivity may becausedby for
examplechanges in water floworincreasing/decreasing pollutionor salinization.
The conductivity is measured usinga 4-electrode measuring cell. This type of measuring cell is
relatively insensitivetosensor fouling, thus keeping maintenancetoaminimum. Themeasuring cell
combined withthe selected measurementmethodresults inanelectrolysis-free measurement system.
The CTD-Diver measures the conductivity of a solution. The CTD-Diver can be programmed to
measureeitherthe true conductivity orthespecificconductivity.Thespecific conductivity is defined
as the conductivity as if the temperature is 25 °C. This setting must beprogrammed prior to starting
the CTD-Diver.
The conductivity of aliquid depends onthe type ofions inthe liquid and to asignificant degree on the
Thisdependency is indicated on thepackaging ofthe calibration solution. The
diagrambelow displays theconductivity as a functionoftemperature for threedifferentcalibration
liquids. The specified valueof the calibration liquid isthe conductivity of theliquid at 25 C.

©May 2022VanEssenInstruments.Allrightsreserved. www.vanessen.com
5
Asa ruleof thumb,itcanbeassumed thatconductivity variesby2%foreach 1 Cchange in
temperature. This means that a calibration solution rated 5 mS/cm (at 25 C)has a conductivity of
approximately 4mS/cm at15 C.
The tablebelow lists several typicalconductivity values for various typesof water.
Type
Conductivity [mS/cm]
Tap water
0.2 0.7
Groundwater
2-20
Seawater
50-80
1.5.1 SpecificConductivity
Thespecific conductivity ofan electrolytesolution isdefined asthe conductivity ifthe solutionisata
certain reference temperature.The specific conductivity is an indirectmeasure of thepresence of
dissolvedsolids such as chloride,nitrate, phosphate,and iron,andcanbeused asanindicator of
waterpollution.
The followingequation isused forcalculating thespecific conductivity KTref fromthemeasured
conductivity K.
  
󰇛󰇜  (5)
where:
KTref = Specific conductivity at Tref
K = Conductivity at T
Tref = Reference temperature (25 °C)
T =Sample temperature
θ=Temperaturecoefficient(1.91 %/°C)

©May 2022VanEssenInstruments.Allrightsreserved. www.vanessen.com
6
Thetemperature coefficient used intheCTD-Diver is1.91 %/°C andthe reference temperature is 25°C.
Thesettingto measure conductivityor specific conductivity canbeprogrammed into theCTD-Diver
bytheuser.
CTD-DiverModel
The Diver models described inthis manual are from the DI28x Series: the CTD-Diver.TheCTD-Diver
measuresabsolute pressure, temperature and conductivity.
CTD-Diver
This Diveris manufactured using a zirconia (ZrO2) casing with a22mm
diameter. The CTD-Diver canstore a maximum of144,000
measurements (date/time,pressure, temperature and conductivity)in
itsworking memory and 144,000 measurements initsbackupmemory.
The CTD-Diversamples pressure, temperature and conductivity and has
the followingmeasurement options:
•Fixed length intervals in fixed length or continuous memory.
•Average values.
•Pre-programmed or user-defined pump tests.
•Event-based. The CTD-Diver only storesmeasurements once
theuser-adjustable variation limit setfortheconductivity
measurement is exceeded.
The CTD-Diver isavailable in the following pressureranges: 10 m, 50 m,
100 mand 200m.
FactoryCalibrationProcedure
EachCTD-Diver is calibrated for pressure,temperatureand conductivity:
1. FirsttheCTD-Diver isindividually calibratedandtested at severaltemperatureandpressure
values toensure superiorperformance. The CTD-Diver is calibrated forthe lifetime of the
instrument, as long as itis usedwithinitsspecified range.
2. Then the conductivity sensor is individually calibrated and tested at several conductivity
values. Thefactory calibration is storedpermanently in theCTD-Diver.
A calibration certificate isavailable upon request.